#include<stdio.h>
#include<conio.h>
#include<math.h>
int main(){
	float sum=1,n;
	printf("nhap vao n: ");
	scanf("%f",&n);
	for(float i=1;i<=n;i++){
	sum=sum+(1/(2*i));
    } 
	printf("\ntong can tinh la: %0.2f",sum);
	getch();
}
